Silk consists of two types of proteins, silk fibroin and sericin. Sericin contributes about 20-30 per cent of total cocoon weight. It is characterized by its high content of serine and 18 amino acids, including essential amino acids. There are different methods of isolation of sericin from silk thread. Solubility, molecular weight, and gelling properties of sericin depend on the method of isolation. It has wide applications in pharmaceuticals and cosmetics such as, wound healing, bioadhesive moisturizing, antiwrinkle and antiaging.